South Korea has successfully test-fired an extended range ballistic missile and will develop a longer range missile capable of striking all parts of North Korea, Seoul's defense ministry said Friday.

South Korea currently operates Hyunmoo ballistic missiles with a range of 300 kilometers, and has been developing longer range missiles to beef up its defense against Pyongyang under a new missile deal with the United States.

The guidelines revised in October 2012 allow Seoul to extend the maximum range of its ballistic missiles from 300 km to 800 km. It limits the maximum payload to 500 kg for 800-km range missiles, while allowing heavier payloads for missiles with shorter ranges.

"The missile development is part of follow-up measures after South Korea and the United States revised the missile guidelines," ministry spokesman Kim Min-seok said in a briefing. "We are now developing 500-km ballistic missiles and plan to make 800-km missiles in the future." He didn't elaborate on the deployment schedule.

The state-funded Agency for Defense Development on March 23 tested a ballistic missile with a range of 500 km and a payload of 1 ton at a firing range in Taean, South Chungcheong Province, and it hit the intended target, a senior official said.

Following the deployment of the 500-km range missile next year, the military plans to develop an 800-km missile with a payload of 500 kg and test-fire it the same year, the official said.

The latest move comes in response to rising risks from the communist rival, which has fired short-range rockets and missiles as well as mid-range missiles in the past few weeks in response to the ongoing joint military exercise between Seoul and Washington.

Pyongyang has deployed various ranges of ballistic missiles, which are capable of striking South Korea, Japan and U.S. Pacific bases, while developing intercontinental ballistic missiles.

Seoul officials believe the North has not yet mastered the technology to produce a nuclear-tipped ICBM capable of hitting the U.S. mainland. (Yonhap)